Shoe stitching machine



May 31, 1949. c. N. LESTAKIS SHOE STITCHING MACHINE 2 Sheets-Sheet 1 Filed July 25, 1946 2 Sheets-Sheet 2 c. N. LESTAKIS SHOE STITCHING MACHINE May 31,1949.

Filed July 7 25, 1946 Patented May 31, 1949 UN [TED STATES 'OIFFflCE SHOE 'STIICHING 'MAGHINE flhristy :N. Lestakis, iPortland 0reg.

Application July 25, 1946, "Serial No.686;'053

SClaims. #My invention relates to machines especially adapted to stitch parts "of shoes such as "the toe caps thereof and has tor-"its main objective the turn impartsan oscillating-movement to a lever of the first class the bottomendof which is=-connected io a rack-'engaginga pinion secured 17043118 bottom 0f a "circular bobbin'carrier having hookattached to its peripheral surface.

011 machines adapted to form a lock stitch,

thread from a spool is threaded thruthe tension device and "needle eye and thread from the bobbin is brought up 'thru "the hole provided for the needle to enter the top of the machine arm.

The machine needle during its reciprocating movement enters this *hole in the outer end of the arm- -carrying thread from the spoolwith it. Just as the needle starts its 'upward movement -it*-hesitates ier an "instant *andinso doing causes the thread to 100p 0litlW8.Tdly*fI'Om the needle. The hook on the bobbin carrier picks up this loop before releasing it carries it around to a positionto receive the threadfrom the bottom bobbin in its big ht thus forming a lock stitch.

The foregoing operation is well "known to all versed in theoperation of sewing machines and is recited as preliminary-to what iollows. It is apparent that the bobbin-must bevery limited in size. As a matter of fact this "bobbin "has a caoacii'iy "of about l0 lineal ie'etof thread in machines now in use.

As a consequence the "bobbin must be replenished often; It'seemsthat' the thread always runs out in the middle .of a jobnrurih to the exasperation Ofth'e .shoemaker. Ithavefound anew way "to increase-theamount 'ofthrea d that may he carried by a :bo'bbin without increasing the size of the arm of the stitching machine. How I accomplish the above is illustrated. in the accompanying drawings and minutely described in the specification.

Fig. '1 oflthe drawings (is a vertical section on approximately the .ceriterline of the arm; Fig. "2 is a'horizontal section on'the line 2- 2 of Fig. 1;

Fig. 25A is a:iragmental-e1evational view of the lever shown in section :in Fig; :2 Fig. 13 is x a plan showing the transfer of t-he thread loop from one hook to the other; Fig. 4"is a vertical section on line "4-:dwofTlig. 52-;- Fig. 5- -is "a "vertical section on line IF-5 or iliiig. 2; Fig. 16 dis -a "vertical section on line 16 46 oi'LFlig. T2; IEig. '7 is a plan view of 'thebobbin carrier; *Eig. 8 ;is an elevation of the reciprocating lloop icarr'ien; lFig. 9'is a vertical section of :a. :needle showing the forming or the threadilo'op; 101is a diagrammatical "elevation 1 showing. theirelation-oithe thread loop and the bobbin warrior.

.Thruout the :drawings and :the specification similar lnumerals irefer torsimilar parts;

The .drawings ane made "on a scale twice the size-of'the finishedlpro'ductin order to more clearl-y illustrate the 'rzelationnf *the parts without undue crowding.

Since :my inventionx'relates to only a small part of the .shoe stitching machine mechanism it has been designed for adaptation to machines now in use.

"wherefore, in.:lieu :ofrzconnecting the customary :nack bar of apresentmahines 150 the :camoper- :ated oscillating :l'ever, it connect my hook bar or loop carrier-12 inyithe umannerrshown in Fig. 2. This .hook bar 2115 an elongated structure provided at one end with the jaw 3 for connection to the lever 1 and having -at the other end a hook carrying iportion '4 hingedl-y connected itheretdby means aof the 'hinge pin 5. The free end :of this'hinged portion 4 terminates in a .hook 6 ithe :stnucturenf which is more clearly shown in Figs. 72 and- 8. In these :figures it is :to .be noted that the hook $6 is biiurcated with "the divided :portions Tispaced-apart for the purpose later to *be described.

The atmxcasingdfl withinwhichthe hook bar 2 l'swlGCilIJlOBfiilEdiihfiiS cits send :9? curved 'so "that the hinged end portion il will be deflected to bring the hoolc'e toarposition=to -the-1eft and slightly behind the needle Hi. This needle Hi, shown in mg. f9, isltheasame tas .us'eduiin the prior-art and is provided with two :groovesl 1| -and lz :positioned diametrically opposite 53nd above the needle eye =1 In. practice positionithe short groove 12 facing the hinged end portionve so that'the thread "I4'Wi11i1000 .outtoward'sa-id portion A whereby the loop 1:5 "may lreadily :beengaged by the book 6' whose point .iscaused to lpass'close' to the needle H) by 'the raised portion 16 formed on the inside curved surface *9 of the casing 8. The hinged end -portionfl of thekhookbar 2 is kept from moving too close. to "the needle by that portion ll adjacent to and rearward of the hinge pin 5 which portion H is shaped to engage the grooved guiding portion l8 of the casing 8 whereby to limit the movement of the hook 6 to a predetermined path during its travel in either direction.

The hook bar 2 is provided with a pin 19 which projects from the upper face 20 of said bar 2 and into an elongated slot 2| formed in the bottom face 22 of an elongated cam bar 23. This slot 2! limits the movement of the cam bar 23 by the reciprocating hook bar 2. This cam bar 23 is positioned above the hook bar 2 and the movement of both bars is limited to a guideway formed by the surface 24 and 25 of the arm casing 3, the guide lugs 26 formed as a part of said casing 8, and the top cover plate 21. The cam bar 23 has a cam arm 28 projecting from one end thereof. This cam arm 28 engages a pin 29 projecting from the top face of a horizontally revolvable disk 39 pivotally mounted on the pin 3| projecting upwardly from the bottom surface 25 of the casing 8. Extending from the peripheral face of the disk as is a hook 32 which is so positioned that itwill pass between the bifurcated portions I of the hook 6 on the hook bar 2.

The forward inoperative or rest position of the cam arm 28 is forward of the pin 29. On the backward movement of the hook bar 2 its pin l9 engages the end 28A of the slot 2! in the cam bar 23 whereby both bars move backwardly simultaneously whereupon the cam arm 28 engages the pin 29 and causes the disk 39 to rotate clockwise.

The various members of the apparatus are positioned and synchronized so that the hook it on the hook bar 2 will be in the position (shown in Fig. 3) or radially aligned with the hook 32 on the disk 39. In practice, when the above occurs, the hook 3 will be extending the loop [5 formed by the needle I due to its peculiar construction and operation. This extended loop is clearly shown in Fig. 10.

It is apparent that the hook 32 travels pi/ times the distance the hook 6 travels hence the hook 32 will engage the loop l as said hook 32 passes between the bifurcated portions 1 of the hook 6 and carry said loop l5 away and upwardly from the hook 8. This upward movement of the hook 32 will continue until the cam arm 28 passes under and to the rear of the pin 29 on the disk 39. When this point is reached, or at the end of the backward travel of the hook bar 2, the disk 30 is caused to rotate counterclockwise to its former inoperative or rest position thru the action of the spiral spring 33 positioned above the disk 39 with one of its ends fixed in that portion of the pin 3| which projects above the top face of the disk 33 and the other end looped about a pin 34 projecting from the top face of the disk 30. This counterclockwise rotation of the disk 39 is limited and cushioned by a leaf spring 35 one end of which is secured to the casing 8 by the screws 36 as shown in Fig. 2.' As the hook 32 moves counterclockwise a tension is held on the loop I5 by the tension apparatus with which all sewing machines is provided. This tension de-' vice has not been illustrated but is well understood by those skilled in the art.

On the forward movement of the hook bar 2 the cam arm 23 engages the pin 29 from its rearward side and the portion 28A raises the hook 32 to the dotted position of said hook shown in Fig. 2. When the hook 32 is in this position the loop I5 is readily released whereupon it is shortened in the well known manner by the tension device of the machine. It is to be noted that at the point of release the loop [5 is to the right of the pointed end 3? of the bobbin carrier 38. A perusal of the drawings, Figs. 1, 2, '7, and 10, will show that the loop it can be readily transferred from the left to the right hand side of the bobbin carrier and that the thread 39 coming from the top of the bobbin carrier will be caught in the bight of the loop l5 which is a necessity in the forming of a lock stitch.

This thread 39 is carried on the bobbin 4B positioned within the bobbin carrier 38. This bobbin carrier 38 is formed in two sections 4| and 42 telescoped together when assembled. The engaging portions 33 and 44 are offset to form a smooth exterior surface. The section 4| has a slot 45 which extends beyond the section 42 when the bobbin carrier is assembled so that the end of the thread 39 may be brought to the exterior of the bobbin carrier without threading it thru a hole. The thread 39 is led from the bobbin 4!! out thru the bobbin carrier 38 and out thru the needle hole 43 in the top cover plate 21 as is the usual practice. A tension spring 41 is provided on the bobbin carrier section 42 under which the thread is withdrawn.

The bobbin carrier 38 rests in a cradle 48 formed in the bottom surface 25 of the casing 8 and it is further confined in position by the rearward stop 4-3 and the forward stop 50 both formed integral with the casing 8. The bobbin carrier 38 is loosely confined so that the thread 39 may be freely withdrawn from its bobbin 49 and so that the loop 55 may readily pass under and over said carrier as said loop I5 is moved from the left to the right hand side thereof.

The bobbin used on prior art machines is in diameter and /4" between flanges. The bobbin 33 shown in the illustrations is /8 in diameter and 2 between the flanges yet the machine arm casing 3 is narrower than in the prior art machines. The capacity may be further increased by increasing the movement of the operating lever I.

It is apparent without further illustration that the book 3 may be made without the bifurcated portions and that the hook 32 may be made with them. It is also apparent that the design and arrangement of parts may be changed and modified over that shown and described hence I do not limit my invention to the exact illustrations and description herein but extend it to all that comes fairly within the scope of the appended claims.

What I claim as new over the prior art follows:

1. In a shoe stitching machine provided with a bobbin carrier, means for transferring a thread loop formed by said machine from one side of the bobbin carrier to the other which includes a reciprocable bar provided with a hook to engage a loop positioned on one side of the bobbin carrier, means for reciprocating the hook bar, a cam bar periodically operable by the hook bar, and means operable by the cam barto remove a loop from the hook bar hook and torelease it on the opposite side of the bobbin carrier.

2. In a shoe stitching machine the combination of, an arm, a needle, adjacent the end of the arm, carrying a thread and operable to form a loop in said thread, an elongated bobbin carrier positioned in the arm, an elongated reciprocable bar positioned on one side of the bobbin carrier having a hinged end portion terminating in a hook, means to guide said hook to a position with respect to the needle to engage a loop formed thereby, means for reciprocating said bar, a cam bar periodically operable by the hook bar, and means operable by the cam bar to remove a loop from the hook bar hook and to release it on the opposite side of the bobbin carrier.

3. In a shoe stitching machine the combination of, an arm, a needle, adjacent the end of the arm, carrying a thread and operable to form a loop in said thread, an elongated bobbin carrier positioned in the arm, an elongated reciprocable bar positioned on one side of the bobbin carrier having a hinged end portion terminating in a hook, said bar, hinged portion, and arm, having portions adapted to guide said hook to a position with respect to the needle to engage a loop formed thereby, means for reciprocating said bar, a cam bar periodically operable by the hook bar, and means operable by the cam bar to remove a loop from the hook bar hook and to release it on the opposite side of the bobbin carrier.

4. In a shoe stitching machine the combination of, a needle carrying a thread and operable to form a loop in said thread, a bobbin carrier, a reciprocable bar positioned on one side of the bobbin carrier and provided with a, hook adapted to engage a loop formed by the needle, means to reciprocate said bar, means having rotative movement and provided with a hook adapted to remove a loop from the hook bar hook and release it on the opposite side of the bobbin carrier, and means operable by the hook bar to periodically cause said rotative movement.

5. In a shoe stitching machine provided with a needle carrying a thread and operable to form a loop in said thread, a bobbin carrier, a bar on one side of the bobbin carrier having a pin projecting therefrom and a hinged end portion terminating in a hook adapted to engage a loop formed by the needle, means for reciprocating the hook bar, a rotatively mounted disk having a pin projecting therefrom and a hook adapted to engage a loop carried by the hook bar and remove it therefrom, a cam bar provided with an elongated slot for the reception of the pin on the hook bar and having a cam arm projecting therefrom for engagement with the disk pin to cause rotative movement of the disk in one direction whereby its book is operable to engage and remove a loop carried by the hook bar hook, and means to cause rotative movement of the disk in the opposite direction to permit the disk hook to carry the loop to the opposite side of the bobbin carrier and release it.

CHRISTY N. LESTAKIS.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Number Name Date 331,107 Arnold Nov. 24, 1885 1,158,937 Krautsch Nov. 2, 1915 

